ASHRAE-90.1-2022- - Page 381
Extracted Content
Table L2.2.3 Proposed Building HVAC System Parameters (Continued)
| Category | Parameter | Fixed or User Defined | Required | Applicable Systems a |
|---|---|---|---|---|
| System Fan Power and Controls | Design fan power, W/cfm | User defined | Input electric power for all fans required to operate at_fan system design conditions_ divided by the supply airflow rate. Include any VSD losses at design condition. This is a wire-to-air value, including all drive, motor_efficiency_, and other losses. | All |
| System Fan Power and Controls | Part-load fan controls: • Constant volume • Two-speed or three-speed, then input: • W/cfm at each speed • % cfm at leach speed • VAV | User defined | Static pressure_reset_ included for_VAV_ | All (constant volume, two speed) 9, 10, 11 (VAV) |
| Variable-Air- Volume Systems | SAT controls (select): • None • OAT SAT_reset_ • Warmest zone SAT_reset_ | User defined | If not SAT_reset_, then constant at 55°F. Options for_reset_ based on OAT or warmest zone. If OAT_reset_, SAT is_reset_ higher to 60°F at outdoor low of 50°F. SAT is 55°F at outdoor high of 70°F. If warmest zone, then the user can specify the minimum and maximum temperatures. | 9, 10, 11 |
| Variable-Air- Volume Systems | • Zone minimum damper and_Evs_ • Standard 62.1 simple method except for schools | Fixed | • Schools: 1.2 ×Voz zone minimum design_ventilation_ rate, cfm;Evs = 0.65 • Other_buildings_: Simple Standard 62.1 method is 1.5 ×Voz zone minimum design ventilation rate, cfm;Evs = 0.75. | 9, 10, 11 |
| Variable-Air- Volume Systems | Dual_set point_ minimum_VAV_ damper position | User defined | Heating minimum and maximum airflow fraction | 9, 10, 11 |
| Variable-Air- Volume Systems | Terminal-unit heating source | User defined | Electric or hydronic | |
| Variable-Air- Volume Systems | FPTU type | User defined | Series or parallel FPTU | 11 |
| Variable-Air- Volume Systems | Parallel FPTU fan | Sized for 50% peak primary air at 0.35 W/cfm | 11 | |
| Variable-Air- Volume Systems | Series FPTU fan | Fixed | Sized for 50% peak primary air at 0.35 W/cfm | 11 |
| Economizer | OSA economizer presence | User defined | Yes or no | 3, 4, 5, 6, 9, 10, 11 |
| Economizer | Economizer high limit | Fixed | • Lockout on differential dry-bulb temperature (OAT > RAT) in Climate Zones 6A, 5A, All B, and C • Fixed enthalpy > 28 Btu/lb or fixed dry-bulb OAT > 75°F in Climate Zones 0A to 4A | |
| Energy Recovery | Sensible effectiveness | User defined | Heat exchanger sensible effectiveness at design heating and cooling conditions | 3, 4, 9, 10, 11, 12 |
| Energy Recovery | Latent effectiveness | User defined | Heat exchanger latent effectiveness at design heating and cooling conditions | 3, 4, 9, 10, 11, 12 |
| Energy Recovery | Bypass SAT_set point_ | User defined | If bypass, target supply air temperature | 3, 4, 9, 10, 11, 12 |
| Energy Recovery | Fan power reduction when in bypass | User defined | If bypass, specify fan power reduction, W/cfm. | 3, 4, 9, 10, 11, 12 |
a. Applicable systems from Table L.1.1.1 Informative Note: See Section 3.3 for a full list of terms used in this table.